Tissue fusion (tissue connection), especially in the form of anastomoses and ligations (ligatures), can be carried out by various techniques, for example, suturing techniques and stapling techniques.
Newer tissue fusion techniques provide for the use of ultrasound, laser irradiation, or heat. Although carrying out those techniques brings about tissue fusion which is reliable and safe from a medical point of view, the disadvantage is that part of the tissue in the fusion region always also becomes degenerated because of the energy input. In some circumstances, this can have an adverse effect on the strength and tightness of the fused tissue.
WO 2011/138347 A2 discloses a surgical system for electrosurgical tissue fusion comprising not only a surgical instrument having two high-frequency current electrodes (HF electrodes), but also a medically compatible material supporting the tissue connection. The material can be, in particular, a collagen disc.
The use of a biocompatible material layer as intermediate layer between body tissue surfaces to be fused is disclosed in DE 10 2009 002 768 A1.
A fundamental disadvantage of the known tissue fusion materials is the application thereof into a tissue region to be fused, that application being very complicated in some cases. A further difficulty is that of achieving a most uniform distribution of the materials in a tissue region to be fused. Moreover, a possible result of inhomogeneities with regard to the material thickness is that the material contracts with great variation upon input of energy. Hence, there is the risk of there being insufficient material provided for strong and tight tissue fusion.